JP6228013B2 - Method for producing lubricating base oil - Google Patents

Description

  The present invention relates to a method for producing a lubricating base oil.

  Among petroleum products, for example, lubricating oil is a product in which fluidity at low temperatures is regarded as important. For this reason, the base oil used in these products must have wax components such as normal paraffin, which cause low-temperature fluidity deterioration, either completely or partially removed or converted to something other than wax components. Is desirable.

  As a dewaxing technique for removing the wax component from the hydrocarbon oil, for example, a method of extracting the wax component with a solvent such as liquefied propane or MEK is known. However, this method has problems such as high operating costs.

  On the other hand, as a dewaxing technique for converting a wax component in a hydrocarbon oil into a non-wax component, for example, a hydrocarbon oil can have a dual function of hydrogenation-dehydrogenation ability and isomerization ability in the presence of hydrogen. There is known an isomerization dewaxing method in which a normal paraffin in a hydrocarbon oil is isomerized into an isoparaffin by contacting with a hydroisomerization dewaxing catalyst having (see, for example, Patent Document 1).

JP-T-2006-502297

  There are a plurality of types of lubricant base oil products depending on the purpose of use, and low temperature performance and viscosity characteristics required for each product are different. Therefore, it is desirable to obtain a large fraction corresponding to the target product.

  For this reason, hydrogenated feedstocks are conventionally used in the production of lube base oils that contain heavier fractions (heavy fractions) than the fraction corresponding to the target product (product fractions). A method is known in which the above-described isomerization dewaxing is performed after decomposing and lightening a heavy component.

  INDUSTRIAL APPLICABILITY The present invention can efficiently obtain a lubricating base oil having excellent viscosity characteristics from a raw material oil containing a heavy component having 30 or more carbon atoms and optionally also containing a sulfur component and a nitrogen component. An object of the present invention is to provide a method for producing a lubricating base oil.

  In the present invention, the content of the heavy component having 30 or more carbon atoms is 80% by mass or more, and the partial pressure of hydrogen is 5 to 20 MPa so that the decomposition rate of the heavy component is 20 to 85% by mass. Hydrocracking under conditions to obtain a hydrocracked oil containing the heavy fraction and hydrocracked product thereof, and a base oil fraction containing the hydrocracked product from the hydrocracked oil A second step of fractionating the heavy fraction containing the heavy fraction and heavier than the base oil fraction, and the base oil fraction fractionated in the second step. A third step of obtaining a dewaxed oil by isomerization and dewaxing, wherein the heavy fraction fractionated in the second step is used as part of the feedstock in the first step. The present invention relates to a method for producing a lubricating base oil.

  1 aspect of this invention WHEREIN: The content rate of the sulfur content in the said raw material oil may be 0.0001-3.0 mass%.

  In one aspect of the invention, a method for producing a lubricating base oil includes a fourth step of hydrorefining the dewaxed oil obtained in the third step to obtain a hydrorefined oil, and the fourth step. And a fifth step of fractionating the hydrorefined oil obtained in the step to obtain a lubricating base oil.

In the above aspect, in the fifth step, it is preferable to obtain a lubricating base oil having a kinematic viscosity at 100 ° C. of 3.5 mm ² / s to 4.5 mm ² / s and a viscosity index of 120 or more.

  In one aspect of the present invention, the feedstock oil may contain slack wax having a 10 vol% distillation temperature of 500 to 600 ° C and a 90 vol% distillation temperature of 600 to 700 ° C. In the first step, the hydrocracking is preferably performed so that the decomposition ratio of the heavy component is 25 to 85% by mass.

  In one embodiment of the present invention, the feedstock oil may contain slack wax having a 10 vol% distillation temperature of 400 to 500 ° C and a 90 vol% distillation temperature of 500 to 600 ° C. In the first step, the hydrocracking is preferably performed so that the decomposition ratio of the heavy component is 20 to 80% by mass.

  In one embodiment of the present invention, the hydrocracking is performed in the presence of hydrogen in a porous inorganic oxide containing two or more elements selected from aluminum, silicon, zirconium, boron, titanium, and magnesium, and It can be carried out by contacting the above raw material oil with a hydrocracking catalyst containing one or more metals selected from Group 6 and 8-10 elements of the periodic table supported by a porous inorganic oxide. .

  In one embodiment of the present invention, the third step may be a step of contacting the base oil fraction with a hydroisomerization dewaxing catalyst to obtain the dewaxed oil, wherein the hydroisomerization dewaxing is performed. The catalyst contains a zeolite having a 10-membered ring one-dimensional pore structure, a support containing a binder, and platinum and / or palladium supported on the support, and the amount of carbon is 0.4 to 3.5. It may be a hydroisomerization dewaxing catalyst having a mass%, and the zeolite contains an organic template and an organic template-containing zeolite having a 10-membered ring one-dimensional pore structure, containing ammonium ions and / or protons. It may be derived from an ion exchange zeolite obtained by ion exchange in a solution.

  In the aspect of the present invention, the third step may be a step of obtaining the dewaxed oil by bringing the base oil fraction into contact with a hydroisomerization dewaxing catalyst. The dewaxing catalyst contains a zeolite having a 10-membered ring one-dimensional pore structure, a support containing a binder, and platinum and / or palladium supported on the support, and has a micropore volume of 0.02. The zeolite may be a hydroisomerization dewaxing catalyst of ˜0.12 ml / g, and the zeolite contains an organic template and an organic template-containing zeolite having a 10-membered ring one-dimensional pore structure, ammonium ions and / or Alternatively, it may be derived from an ion exchange zeolite obtained by ion exchange in a solution containing protons, and the micropore volume per unit mass of the zeolite is 0.01 to 0.12 ml / g. There may be. In the present specification, the micropore refers to a “pore having a diameter of 2 nm or less” defined by the International Union of Applied Chemistry IUPAC (International Union of Pure and Applied Chemistry).

  According to the present invention, it is possible to efficiently obtain a lubricating base oil having excellent viscosity characteristics from a raw material oil containing a heavy component having 30 or more carbon atoms and optionally also containing a sulfur component and a nitrogen component. A possible method for producing a lubricating base oil is provided.

It is a flowchart which shows an example of the lubricating base oil manufacturing apparatus which enforces the manufacturing method of the lubricating base oil of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  In the method for producing a lubricating base oil according to the present embodiment, a heavy oil decomposition ratio of 20 to 85% by mass with respect to a raw material oil having a heavy content of 30 or more carbon atoms is 80% by mass or more. Thus, the first step (hereinafter referred to as “hydrocracking step” in some cases) to perform hydrocracking under conditions of hydrogen partial pressure of 5 to 20 MPa to obtain a hydrocracked oil containing a heavy fraction and its hydrocracked product And a desired base oil fraction containing a hydrocracked product, and a heavy fraction heavier than the base oil fraction containing a heavy fraction, respectively. 2 step (hereinafter referred to as “first separation step” in some cases) and a third step (hereinafter, in some cases) to obtain dewaxed oil by isomerization and dewaxing the fractionated base oil fraction. "Dewaxing step"). In the present embodiment, the heavy fraction fractionated in the second step can be supplied to the first step as part of the feedstock.

  In this embodiment, a lubricating base oil can be obtained from the dewaxed oil obtained in the third step by a known method. That is, according to the manufacturing method which concerns on this embodiment, lube base oil can be manufactured efficiently by obtaining dewaxed oil from a heavy part with 30 or more carbon atoms through the above-mentioned steps.

  In addition, the production method according to this embodiment is a fourth step (hereinafter referred to as “hydrorefining step” in some cases) to obtain a hydrorefined oil by hydrotreating the dewaxed oil obtained in the third step. And a fifth step of fractionating the hydrorefined oil to obtain a lubricating base oil (hereinafter sometimes referred to as “second separation step”).

  Hereinafter, each step will be described in detail.

(Hydrolysis process)
In the hydrocracking step, the hydrogen partial pressure of 5 to 20 MPa is applied so that the cracking rate of the heavy component is 20 to 85% by mass with respect to the feed oil having a heavy component content of 30 or more carbon atoms of 80% by mass or more. Hydrocracking oil containing heavy components and hydrocracked products thereof is obtained.

In the present specification, heavies decomposition rate (% by mass), the heavies content of the number of 30 or more carbon atoms in the feedstock and C _1, hydrogenolysis obtained through hydrogenolysis when the content of the heavy fraction having 30 or more carbons in the oil was _{C 2,} can be obtained by _{((C 1 -C 2) /} C 1) × 100.

  In the hydrocracking process, the heavy component is converted to a hydrocarbon having a lower boiling point than the heavy component. Some of these are base oil fractions suitable for lubricating base oil applications, and the other parts are lighter fractions lighter than the base oil fraction (for example, including fuel oil fractions and solvent fractions). It is. Moreover, the other part (15-80 mass%) of a heavy part does not fully receive hydrocracking, but remains in hydrocracked oil as an undecomposed heavy part. The “hydrocracked oil” refers to the entire hydrocracked product containing undecomposed heavy components unless otherwise specified.

  The content ratio of the heavy oil having 30 or more carbon atoms is 80% by mass or more, preferably 85% by mass or more. In addition, the content ratio of the hydrocarbon having 30 to 60 carbon atoms in the raw material oil is preferably 65% by mass or more, and more preferably 70% by mass or more.

  The upper limit of the content ratio of the heavy component having 30 or more carbon atoms in the raw material oil is not particularly limited, and may be, for example, 100% by mass. Moreover, the upper limit of the content ratio of hydrocarbons having 30 to 60 carbon atoms in the feed oil is not particularly limited, and may be, for example, 100% by mass.

  In addition, the carbon number distribution of hydrocarbons in the feedstock oil can be measured using a gas chromatograph.

  The feedstock oil is preferably a petroleum-derived hydrocarbon oil containing petroleum-derived hydrocarbon. As petroleum-derived hydrocarbon oil, for example, vacuum gas oil and its hydrorefined oil, vacuum gas oil hydrocracked oil, atmospheric residue hydrocracked oil, vacuum residue hydrocracked oil, slack wax (crude wax), Mentioned waxy oil, deoiled wax, paraffin wax, microcrystalline wax, solvent extracted raffinate.

  The vacuum gas oil is a distillate obtained from a crude oil vacuum distillation apparatus, and is a hydrocarbon oil having a boiling range of about 350 to 550 ° C. The atmospheric residual oil is a bottom oil extracted from an atmospheric distillation apparatus and is a hydrocarbon oil having a boiling point range of 350 ° C. or higher. Further, the vacuum residue is a tower bottom oil extracted from a vacuum distillation apparatus, and is a hydrocarbon oil having a boiling point range of 550 ° C. or higher. A vacuum gas oil hydrocracked oil is a hydrocarbon oil obtained by hydrocracking a vacuum gas oil, an atmospheric residue hydrocracked oil is a hydrocarbon oil obtained by hydrocracking an atmospheric residue, The vacuum residue hydrocracked oil is a hydrocarbon oil obtained by hydrocracking a vacuum residue.

  The feedstock oil may be a mixture of the above-described petroleum-derived hydrocarbon oil and a heavy fraction (hereinafter, referred to as “recycled oil” in some cases) fractionated in the second step described later.

  The raw material oil may contain a sulfur content, and the content ratio of the sulfur content may be, for example, 0.0001 to 3.0 mass%, or 0.001 to 1.0 mass%, 0.01-0.5 mass% may be sufficient. In this embodiment, since desulfurization proceeds with hydrocracking of the feedstock in the hydrocracking step, even if the feedstock contains sulfur in the above range, the hydroisomerization dewaxing catalyst in the latter stage, etc. Can be sufficiently prevented from being deteriorated by sulfur.

  The raw material oil may contain a nitrogen content, and the content ratio of the nitrogen content may be, for example, 0.0001 to 0.5 mass%, or 0.001 to 0.1 mass%.

Kinematic viscosity at 100 ° C. of the feedstock may be a 6.0~100.0mm ² / s, it may be 7.0~50.0mm ² / s.

  In the hydrocracking step, 20 to 85 mass% of the heavy component is hydrocracked by hydrocracking of the feedstock oil. When the cracking rate of heavy components in the hydrocracking process exceeds 85% by weight, the amount of raw material oil processed per hour increases, but the heavy components are decomposed excessively and light fractions are generated. The yield of oil base oil decreases. On the other hand, when the decomposition rate of the heavy component is less than 20% by mass, the production of the light fraction can be suppressed, while the processing amount per hour of the heavy component decreases. That is, by adjusting the decomposition rate of heavy components by hydrocracking to 20 to 85% by mass, the balance between the processing amount of heavy components and the yield of lubricant base oil becomes good, and the production of lubricant base oil is improved. Efficiency (production per unit time) is improved.

  Further, when the decomposition rate of the heavy component is 10% by mass or more, desulfurization and denitrification in the hydrocracking step sufficiently proceed even when the raw material oil contains sulfur and nitrogen as described above. Therefore, adverse effects on the subsequent hydroisomerization dewaxing catalyst and the like can be sufficiently suppressed.

  On the other hand, when the conditions of the hydrocracking process are set to conditions in which the cracking rate of the heavy component is less than 10% by mass, desulfurization does not proceed sufficiently, and the sulfur content contained in the feedstock is large. Will be served. In this case, in order to prevent a decrease in the catalytic activity of the hydroisomerization dewaxing catalyst or the like, it is necessary to set the conditions for isomerization dewaxing more strictly in the dewaxing step. And by making conditions of isomerization dewaxing strict, the decomposition rate increases and the yield of the target lubricating base oil decreases.

  Furthermore, by performing hydrocracking under the conditions of a hydrogen partial pressure of 5 to 20 MPa so that the cracking rate of heavy components is 20 to 85% by mass, the resulting lubricating base oil has excellent viscosity characteristics. (Viscosity index is high). That is, according to the manufacturing method according to this embodiment, a lubricating base oil having excellent viscosity characteristics can be efficiently obtained by employing a specific hydrocracking step.

  In the hydrocracking process of this embodiment, hydrocracking can be performed by bringing the feedstock into contact with the hydrocracking catalyst in the presence of hydrogen. The hydrocracking catalyst and the hydrocracking reaction conditions were determined by referring to the hydrocracking catalyst described later and the reaction conditions at that time, except that the hydrogen partial pressure was 5 to 20 MPa. Can be appropriately selected within a range of 20 to 85% by mass.

  Specific examples of a suitable hydrocracking catalyst include the following hydrocracking catalyst A.

  The hydrocracking catalyst A includes a porous inorganic oxide containing two or more elements selected from aluminum, silicon, zirconium, boron, titanium and magnesium, and a period supported by the porous inorganic oxide. And one or more metals selected from the elements of Group 6, Group 8, Group 9, and Group 10. According to the hydrocracking catalyst A, even if the raw material oil contains a sulfur content and a nitrogen content in the above-described range, the decrease in catalytic activity due to sulfur poisoning is sufficiently suppressed.

  As the support for the hydrocracking catalyst A, a porous inorganic oxide composed of two or more selected from aluminum, silicon, zirconium, boron, titanium and magnesium as described above is used. The porous inorganic oxide is preferably at least two selected from aluminum, silicon, zirconium, boron, titanium and magnesium from the viewpoint that the hydrocracking activity can be further improved. An inorganic oxide (a composite oxide of aluminum oxide and another oxide) is more preferable. Further, the carrier of the hydrocracking catalyst A may be an inorganic carrier having solid acidity.

  When the porous inorganic oxide contains aluminum as a constituent element, the aluminum content is preferably 1 to 97% by mass, more preferably 10 to 95% by mass in terms of alumina, based on the total amount of the porous inorganic oxide. %, More preferably 20 to 90% by mass. When the aluminum content is less than 1% by mass in terms of alumina, physical properties such as carrier acid properties are not suitable, and sufficient hydrocracking activity tends not to be exhibited. On the other hand, if the aluminum content exceeds 97% by mass in terms of alumina, the solid acid strength of the catalyst becomes insufficient and the activity tends to decrease.

  The method for introducing silicon, zirconium, boron, titanium and magnesium, which are carrier constituent elements other than aluminum, is not particularly limited, and a solution containing these elements may be used as a raw material. For example, for silicon, silicon, water glass, silica sol, etc., for boron, boric acid, etc., for phosphorus, phosphoric acid and alkali metal salts of phosphoric acid, etc., for titanium, titanium sulfide, titanium tetrachloride and various alkoxide salts, etc. As for zirconium, zirconium sulfate and various alkoxide salts can be used.

  Furthermore, the porous inorganic oxide may contain phosphorus as a constituent element. When phosphorus is contained, the content is preferably 0.1 to 10% by mass, more preferably 0.5 to 7% by mass, and still more preferably 2 in terms of oxide, based on the total amount of the porous inorganic oxide. -6 mass%. When the phosphorus content is less than 0.1% by mass, sufficient hydrocracking activity tends not to be exhibited, and when it exceeds 10% by mass, excessive decomposition may proceed.

  It is preferable to add the raw materials for the carrier constituents other than the above-described aluminum oxide in the step prior to the firing of the carrier. For example, after adding the said raw material previously to aluminum aqueous solution, the aluminum hydroxide gel containing these structural components may be prepared, and the said raw material may be added with respect to the prepared aluminum hydroxide gel. Alternatively, the above raw materials may be added in a step of adding water or an acidic aqueous solution to a commercially available aluminum oxide intermediate or boehmite powder and kneading them, but it is more preferable to coexist at the stage of preparing aluminum hydroxide gel. Further, a carrier constituent component other than aluminum oxide may be prepared in advance, and an alumina raw material such as boehmite powder may be prepared therein. Although the mechanism of the effect of the carrier constituents other than aluminum oxide has not necessarily been elucidated, it is presumed that it forms a complex oxide state with aluminum, which increases the surface area of the carrier and the interaction with the active metal. It is considered that the activity is affected by producing the action.

  The porous inorganic oxide as a carrier carries one or more metals selected from Group 6, Group 8, Group 9, and Group 10 elements of the periodic table. Among these metals, it is preferable to use a combination of two or more metals selected from cobalt, molybdenum, nickel and tungsten. Examples of suitable combinations include cobalt-molybdenum, nickel-molybdenum, nickel-cobalt-molybdenum, and nickel-tungsten. Of these, combinations of nickel-molybdenum, nickel-cobalt-molybdenum, and nickel-tungsten are more preferred. In hydrocracking, these metals are used after being converted to a sulfide state.

  As the content of the active metal based on the catalyst mass, the range of the total supported amount of tungsten and molybdenum is preferably 12 to 35% by mass in terms of oxide, and more preferably 15 to 30% by mass. If the total supported amount of tungsten and molybdenum is less than 12% by mass, the active sites tend to decrease and sufficient activity cannot be obtained. On the other hand, if it exceeds 35% by mass, the metal is not effectively dispersed and sufficient activity tends not to be obtained. The total supported amount of cobalt and nickel is preferably 1.0 to 15% by mass, more preferably 1.5 to 13% by mass in terms of oxide. When the total supported amount of cobalt and nickel is less than 1.0% by mass, a sufficient promoter effect cannot be obtained and the activity tends to decrease. On the other hand, if it exceeds 15% by mass, the metal is not effectively dispersed and sufficient activity tends not to be obtained.

  It is preferable that the porous inorganic oxide as a carrier carries phosphorus as an active component together with an active metal. The amount of phosphorus supported on the carrier is preferably 0.5 to 10% by mass, more preferably 1.0 to 5.0% by mass in terms of oxide. If the amount of phosphorus supported is less than 0.5% by mass, the effect of phosphorus cannot be sufficiently exerted, and if it is greater than 10% by mass, the acid property of the catalyst becomes strong and a decomposition reaction may occur. The method for supporting phosphorus on the carrier is not particularly limited, and it may be supported in the aqueous solution containing the metals of Groups 8 to 10 and Group 6 of the periodic table, or before supporting the metal, or You may carry | support sequentially after carrying | supporting.

  The method for incorporating these active metals into the catalyst is not particularly limited, and a known method applied when producing an ordinary hydrocracking catalyst can be used. Usually, a method of impregnating a catalyst carrier with a solution containing a salt of an active metal is preferably employed. In addition, an equilibrium adsorption method, a pore-filling method, an incident-wetness method, and the like are also preferably employed. For example, the pore-filling method is a method in which the pore volume of the carrier is measured in advance and impregnated with a metal salt solution having the same volume. The impregnation method is not particularly limited, and it can be impregnated by an appropriate method according to the amount of metal supported and the physical properties of the catalyst carrier.

  In the present embodiment, the number of types of hydrocracking catalyst A to be used is not particularly limited. For example, one type of catalyst may be used alone, or a plurality of catalysts having different active metal species and carrier components may be used. As a suitable combination in the case where a plurality of different catalysts are used, for example, a catalyst containing cobalt-molybdenum after a catalyst containing nickel-molybdenum, and nickel-cobalt-molybdenum after a catalyst containing nickel-molybdenum are used. Examples thereof include a catalyst containing nickel, a catalyst containing nickel-cobalt-molybdenum after the catalyst containing nickel-tungsten, and a catalyst containing cobalt-molybdenum after the catalyst containing nickel-cobalt-molybdenum. A nickel-molybdenum catalyst may be further combined before and / or after these combinations.

  In the case of combining a plurality of catalysts having different support components, for example, the content of aluminum oxide is included in the subsequent stage of the catalyst having an aluminum oxide content of 30% by mass or more and less than 80% by mass based on the total mass of the support. A catalyst having an amount in the range of 80 to 99% by mass may be used.

  Further, in addition to the hydrocracking catalyst A, a guard catalyst for the purpose of trapping the scale inflow accompanying the base oil fraction or supporting the hydrocracking catalyst A at the separation part of the catalyst bed, if necessary. A demetallizing catalyst or an inert packing may be used. In addition, these can be used individually or in combination.

  The pore volume according to the nitrogen adsorption BET method of the hydrocracking catalyst A is preferably 0.30 to 0.85 ml / g, and more preferably 0.45 to 0.80 ml / g. When the pore volume is less than 0.30 ml / g, the dispersibility of the supported metal becomes insufficient, and there is a concern that the active sites may decrease. Moreover, when the pore volume exceeds 0.85 ml / g, the catalyst strength becomes insufficient, and the catalyst may be pulverized or crushed during use.

  Moreover, it is preferable that the average pore diameter of the catalyst calculated | required by nitrogen adsorption BET method is 5-15 nm, and it is more preferable that it is 6-12 nm. If the average pore diameter is less than 5 nm, the reaction substrate may not sufficiently diffuse into the pores, and the reactivity may be reduced. On the other hand, if the average pore diameter exceeds 15 nm, the pore surface area decreases, and the activity may be insufficient.

  Furthermore, in the hydrocracking catalyst A, the ratio of the pore volume derived from pores having a pore diameter of 3 nm or less in the total pore volume in order to maintain effective catalyst pores and exhibit sufficient activity Is preferably 35% by volume or less.

When the hydrocracking catalyst A is used, the hydrocracking conditions are, for example, a hydrogen pressure of 2 to 20 MPa, a liquid space velocity (LHSV) of 0.1 to 3.0 h ⁻¹ , a hydrogen oil ratio (hydrogen / oil ratio) of 150. To 1500 Nm ³ / m ³ , preferably hydrogen pressure 3 to 15 MPa, liquid space velocity 0.3 to 1.5 h ⁻¹ , hydrogen oil ratio 380 to 1200 Nm ³ / m ³ , more preferably The hydrogen pressure is 4 to 10 MPa, the space velocity is 0.3 to 1.5 h ⁻¹ , and the hydrogen oil ratio is 350 to 1000 Nm ³ / m ³ . These conditions are factors that influence the reaction activity. For example, when the hydrogen pressure and the hydrogen oil ratio are less than the above lower limit values, the reactivity tends to decrease or the catalyst activity tends to decrease rapidly. There is. On the other hand, when the hydrogen pressure and the hydrogen oil ratio exceed the above upper limit values, there is a tendency that excessive equipment investment such as a compressor is required. Further, the lower the liquid space velocity tends to be advantageous for the reaction, but if the liquid space velocity is less than the above lower limit value, there is a tendency that an extremely large internal volume reactor is required and excessive equipment investment is required, When the liquid space velocity exceeds the above upper limit, the reaction tends not to proceed sufficiently. Moreover, 180-450 degreeC is mentioned as reaction temperature, 250-420 degreeC is preferable, 280-410 degreeC is more preferable, 300-400 degreeC is especially preferable. When the reaction temperature exceeds 450 ° C., decomposition to a light fraction proceeds and not only the yield of the base oil fraction decreases, but also the product tends to be colored, and its use as a product base tends to be limited. It is in. On the other hand, when the reaction temperature is lower than 180 ° C., the hydrocracking reaction does not proceed sufficiently, and a heavy decomposition rate of 20 to 85% by mass may not be achieved.

  Here, as one aspect of the hydrocracking step, the feedstock oil is a slack wax (hereinafter referred to as “first”) having a 10 vol% distillation temperature of 500 to 600 ° C. and a 90 vol% distillation temperature of 600 to 700 ° C. It may be referred to as “slack wax”. In such an embodiment, it is preferable to carry out the hydrogenolysis so that the decomposition rate of the heavy component is 25 to 85% by mass. Thereby, a lubricating base oil having excellent viscosity characteristics can be obtained more efficiently.

  In the above aspect, the feedstock oil may include a heavy fraction obtained by subjecting the first slack wax and the first slack wax to the hydrocracking step and the first separation step. That is, when the raw material oil contains a new raw material (fresh feed) and a heavy fraction recycled from the first separation step (recycled oil), the new raw material may contain the first slack wax. preferable. At this time, the amount of the first slack wax in the new raw material is preferably 80% by mass or more, more preferably 90% by mass or more based on the total amount of the new raw material.

The density of the first slack wax at 15 ° C. is preferably 0.89 to 0.92 g / cm ³ , more preferably 0.90 to 0.915 g / cm ³ . Moreover, the 100 degreeC kinematic viscosity of a 1st slack wax becomes like this. Preferably it is 15-30 mm < ² > / s, More preferably, it is 18-28 mm < ² > / s.

  The first slack wax may contain 0.0001 to 3.0% by mass of sulfur. The sulfur content of the first slack wax is preferably 0.0001 to 1.0 mass%, more preferably 0.0001 to 0.5 mass%.

  The first slack wax may also contain 0.0001 to 0.5% by mass of nitrogen. The nitrogen content of the first slack wax is preferably 0.0001 to 0.1% by mass, more preferably 0.0001 to 0.01% by mass.

  In the first slack wax, the content ratio of hydrocarbons having 30 or more carbon atoms (heavy content) is preferably 90% by mass or more, more preferably 95% by mass or more. Further, the content ratio of the hydrocarbon having 30 to 60 carbon atoms is preferably 70% by mass or more, and more preferably 75% by mass or more.

  Further, as another aspect of the hydrocracking step, the feedstock oil is a slack wax (hereinafter referred to as "secondary oil") having a 10 vol% distillation temperature of 400 to 500 ° C and a 90 vol% distillation temperature of 500 to 600 ° C. It may be referred to as “slack wax”. In such an embodiment, it is preferable to carry out the hydrogenolysis so that the decomposition rate of the heavy component is 20 to 80% by mass. Thereby, a lubricating base oil having excellent viscosity characteristics can be obtained more efficiently.

  In the above aspect, the feedstock oil may contain a heavy fraction obtained by subjecting the second slack wax and the second slack wax to the hydrocracking step and the first separation step. That is, when the raw material oil contains a new raw material and the heavy fraction recycled from the first separation step, the new raw material preferably contains the second slack wax. At this time, the amount of the second slack wax in the new raw material is preferably 80% by mass or more, more preferably 90% by mass or more based on the total amount of the new raw material.

The density at 15 ° C. of the second slack wax is preferably 0.83 to 0.89 g / cm ³ , more preferably 0.84 to 0.88 g / cm ³ . Also, 100 ° C. kinematic viscosity of the second slack wax is preferably 5 to 15 mm ² / s, more preferably 6.0~10mm ² / s.

  The second slack wax may contain 0.0001 to 3.0 mass% of a sulfur content. The sulfur content of the second slack wax is preferably 0.0001 to 1.0% by mass, more preferably 0.0001 to 0.5% by mass.

  The second slack wax may also contain 0.0001 to 0.5% by mass of nitrogen. The nitrogen content of the second slack wax is preferably 0.0001 to 0.1% by mass, and more preferably 0.0001 to 0.01% by mass.

  In the second slack wax, the content ratio of hydrocarbons having 30 or more carbon atoms (heavy content) is preferably 85% by mass or more, and more preferably 90% by mass or more. Further, the content ratio of the hydrocarbon having 30 to 60 carbon atoms is preferably 85% by mass or more, and more preferably 90% by mass or more.

(First separation step)
In the first separation step, from the hydrocracked oil obtained in the hydrocracking step, a base oil fraction containing a hydrocracked product (for example, a hydrocarbon having a carbon number of less than 30) and a heavy oil containing a base oil A heavy fraction that is heavier than the fraction is fractionated. In some cases, light fractions such as gas, naphtha, and kerosene are further fractionated.

  The base oil fraction is a fraction for obtaining a lubricating base oil through a dewaxing step (and a hydrorefining step and a second separation step as necessary), which will be described later. It can be changed appropriately depending on the product to be used.

  The base oil fraction is preferably a fraction having a 10% by volume distillation temperature of 280 ° C or higher and a 90% by volume distillation temperature of 530 ° C or lower. By making the base oil fraction into a fraction having a boiling range within the above range, a useful lubricating base oil can be produced more efficiently. In addition, in this specification, 10 volume% distillation temperature and 90 volume% distillation temperature are the values measured based on JISK2254 "petroleum product-distillation test method-gas chromatograph method".

  The heavy fraction is a heavy fraction having a boiling point higher than that of the base oil fraction. That is, the heavy fraction is a fraction having a 10 vol% distillation temperature higher than the 90 vol% distillation temperature of the base oil fraction, for example, a fraction having a 10 vol% distillation temperature higher than 530 ° C. is there.

  In some cases, the hydrocracked oil includes a light fraction (light fraction) having a boiling point lower than that of the base oil fraction in addition to the base oil fraction and the heavy fraction. The light fraction is a fraction having a 90% by volume distillation temperature lower than the 10% by volume distillation temperature of the base oil fraction, for example, a fraction having a 90% by volume distillation temperature lower than 280 ° C.

  The distillation conditions in the first separation step are not particularly limited as long as the base oil fraction and the heavy fraction can each be fractionated from the hydrocracked oil. For example, the first separation step may be a step of fractionating a base oil fraction and a heavy fraction from a hydrocracked oil by vacuum distillation, and atmospheric distillation (or distillation under pressure) and vacuum distillation. May be a step of fractionating the base oil fraction and the heavy fraction from the hydrocracked oil in combination.

  For example, when the hydrocracked oil contains a light fraction, the first separation step includes atmospheric distillation (or distillation under pressure) for distilling the light fraction from the hydrocracked oil, and the atmospheric distillation. The base oil fraction and the heavy fraction can be distilled from each bottom oil by vacuum distillation.

  In the first separation step, the base oil fraction may be fractionated as a single fraction or as a plurality of fractions depending on the desired lubricating base oil. The plurality of base oil fractions thus fractionated can be independently subjected to a subsequent dewaxing step. In addition, a part or all of a plurality of base oil fractions can be mixed and used for the subsequent dewaxing step.

(Dewaxing process)
In the dewaxing step, the base oil fraction fractionated in the first separation step is isomerized and dewaxed to obtain a dewaxed oil. Isomer dewaxing can be performed by contacting the base oil fraction with a hydroisomerization dewaxing catalyst in the presence of hydrogen.

  As the hydroisomerization dewaxing catalyst, a catalyst generally used for hydroisomerization, that is, a catalyst in which a metal having hydrogenation activity is supported on an inorganic support, or the like can be used.

  As the metal having hydrogenation activity in the hydroisomerization dewaxing catalyst, one or more metals selected from the group consisting of metals of Groups 6, 8, 9, and 10 of the periodic table are used. It is done. Specific examples of these metals include noble metals such as platinum, palladium, rhodium, ruthenium, iridium and osmium, or cobalt, nickel, molybdenum, tungsten, iron, etc., preferably platinum, palladium, nickel, Cobalt, molybdenum and tungsten are preferable, and platinum and palladium are more preferable. These metals are also preferably used in combination of a plurality of types, and preferable combinations in that case include platinum-palladium, cobalt-molybdenum, nickel-molybdenum, nickel-cobalt-molybdenum, nickel-tungsten and the like.

  Examples of the inorganic carrier constituting the hydroisomerization dewaxing catalyst include metal oxides such as alumina, silica, titania, zirconia, and boria. These metal oxides may be one kind or a mixture of two or more kinds or a composite metal oxide such as silica alumina, silica zirconia, alumina zirconia, alumina boria and the like. The inorganic carrier is preferably a composite metal oxide having solid acidity such as silica alumina, silica zirconia, alumina zirconia, alumina boria, etc., from the viewpoint of efficiently proceeding hydroisomerization of normal paraffin. The inorganic carrier may contain a small amount of zeolite. Furthermore, the inorganic carrier may contain a binder for the purpose of improving the moldability and mechanical strength of the carrier. Preferred binders include alumina, silica, magnesia and the like.

  The content of the metal having hydrogenation activity in the hydroisomerization dewaxing catalyst is about 0.1 to 3% by mass as a metal atom based on the mass of the carrier when the metal is the above-mentioned noble metal. It is preferable. Moreover, when the said metal is metals other than said noble metal, it is preferable that it is about 2-50 mass% on the mass reference | standard of a support | carrier as a metal oxide. When the content of the metal having hydrogenation activity is less than the lower limit, hydroisomerization tends not to proceed sufficiently. On the other hand, when the content of the metal having hydrogenation activity exceeds the upper limit, the dispersion of the metal having hydrogenation activity tends to be reduced, and the activity of the catalyst tends to be reduced, and the catalyst cost is increased.

  Further, the hydroisomerization dewaxing catalyst is provided on a carrier made of a porous inorganic oxide composed of a material selected from aluminum, silicon, zirconium, boron, titanium, magnesium and zeolite. It may be a catalyst that supports one or more metals selected from Group, Group 9 and Group 10 metal elements.

  Examples of the porous inorganic oxide used as a carrier for such a hydroisomerization dewaxing catalyst include alumina, titania, zirconia, boria, silica, or zeolite. Among these, titania, zirconia, boria, silica and Of those, at least one kind of zeolite and alumina are preferable. The production method is not particularly limited, but any preparation method can be employed using raw materials in various sols, salt compounds, and the like corresponding to each element. Furthermore, once the composite hydroxide or composite oxide such as silica alumina, silica zirconia, alumina titania, silica titania, and alumina boria is prepared, the preparation process in the state of alumina gel and other hydroxides or in an appropriate solution state It may be prepared by adding at any step. The ratio of alumina to other oxides can be any ratio with respect to the support, but preferably alumina is 90% by mass or less, more preferably 60% by mass or less, more preferably 40% by mass or less, preferably Is 10% by mass or more, more preferably 20% by mass or more.

Zeolites are crystalline aluminosilicates such as faujasite, pentasil, mordenite, TON, MTT, ^* MRE, etc., which are ultra-stabilized by the prescribed hydrothermal treatment and / or acid treatment, or contain alumina in the zeolite What adjusted the quantity can be used. Preferably, faujasite and mordenite, particularly preferably Y type and beta type are used. The Y-type is preferably ultra-stabilized, and the ultra-stabilized zeolite by hydrothermal treatment forms new pores in the range of 20 to 100% in addition to the original pore structure called micropores of 20 cm or less. . Known conditions can be used for the hydrothermal treatment conditions.

  As the active metal of such a hydroisomerization dewaxing catalyst, one or more metals selected from Group 6, Group 8, Group 9 and Group 10 elements of the periodic table are used. Among these metals, it is preferable to use one or more metals selected from Pd, Pt, Rh, Ir, and Ni, and it is more preferable to use them in combination. Suitable combinations include, for example, Pd—Pt, Pd—Ir, Pd—Rh, Pd—Ni, Pt—Rh, Pt—Ir, Pt—Ni, Rh—Ir, Rh—Ni, Ir—Ni, Pd— Pt-Rh, Pd-Pt-Ir, Pt-Pd-Ni, etc. are mentioned. Of these, combinations of Pd—Pt, Pd—Ni, Pt—Ni, Pd—Ir, Pt—Rh, Pt—Ir, Rh—Ir, Pd—Pt—Rh, Pd—Pt—Ni, Pd—Pt—Ir Is more preferable, and a combination of Pd—Pt, Pd—Ni, Pt—Ni, Pd—Ir, Pt—Ir, Pd—Pt—Ni, and Pd—Pt—Ir is even more preferable.

  The total content of the active metal based on the catalyst mass is preferably 0.1 to 2% by mass, more preferably 0.2 to 1.5% by mass, and 0.25 to 1.3% by mass as the metal. Even more preferred. If the total supported amount of the metal is less than 0.1% by mass, the active sites tend to decrease and sufficient activity cannot be obtained. On the other hand, if it exceeds 2% by mass, the metal is not effectively dispersed and sufficient activity tends not to be obtained.

  In any of the above hydroisomerization dewaxing catalysts, the method for supporting the active metal on the support is not particularly limited, and a known method applied when producing a conventional hydroisomerization dewaxing catalyst is used. Can be used. Usually, a method of impregnating a catalyst carrier with a solution containing a salt of an active metal is preferably employed. Further, an equilibrium adsorption method, a pore-filling method, an incident-wetness method, and the like are also preferably employed. For example, the pore-filling method is a method in which the pore volume of the support is measured in advance and impregnated with the same volume of the metal salt solution, but the impregnation method is not particularly limited, and the amount of metal supported Further, it can be impregnated by an appropriate method depending on the physical properties of the catalyst support.

  Moreover, the following catalyst can also be used as a hydroisomerization dewaxing catalyst.

<Specific Embodiment of Hydroisomerization Dewaxing Catalyst>
The characteristics of the hydroisomerization dewaxing catalyst of this embodiment are given by being produced by a specific method. Hereinafter, the hydroisomerization dewaxing catalyst of this embodiment will be described in accordance with its preferred production embodiment.

In the method for producing a hydroisomerization dewaxing catalyst according to the present embodiment, an organic template-containing zeolite containing an organic template and having a 10-membered ring one-dimensional pore structure is ion-exchanged in a solution containing ammonium ions and / or protons. A first step of obtaining a support precursor by heating a mixture containing an ion-exchanged zeolite and a binder obtained at a temperature of 250 to 350 ° C. under a N ₂ atmosphere, and a platinum salt and The catalyst precursor containing palladium salt is calcined at a temperature of 350 to 400 ° C. in an atmosphere containing molecular oxygen, and hydroisomerization in which platinum and / or palladium is supported on a support containing zeolite. A second step of obtaining a dewaxing catalyst.

The organic template-containing zeolite used in the present embodiment is a one-dimensional pore composed of a 10-membered ring from the viewpoint of achieving both high isomerization activity and suppressed decomposition activity in normal paraffin hydroisomerization reaction at a high level. It has a structure. Examples of such zeolite include AEL, EUO, FER, HEU, MEL, MFI, NES, TON, MTT, WEI, ^* MRE, and SSZ-32. The above three letters of the alphabet mean the framework structure code given by the Structure Committee of The International Zeolite Association for each classified structure of molecular sieve type zeolite. To do. In addition, zeolites having the same topology are collectively referred to by the same code.

As the above-mentioned organic template-containing zeolite, among the zeolites having the above-mentioned 10-membered ring one-dimensional pore structure, zeolites having a TON or MTT structure, and ^* MRE structures in terms of high isomerization activity and low decomposition activity ZSM-48 zeolite and SSZ-32 zeolite which are zeolites are preferred. ZSM-22 zeolite is more preferable as the zeolite having the TON structure, and ZSM-23 zeolite is more preferable as the zeolite having the MTT structure.

  The organic template-containing zeolite is hydrothermally synthesized by a known method from a silica source, an alumina source, and an organic template added to construct the predetermined pore structure.

  The organic template is an organic compound having an amino group, an ammonium group, etc., and is selected according to the structure of the zeolite to be synthesized, but is preferably an amine derivative. Specifically, at least one selected from the group consisting of alkylamine, alkyldiamine, alkyltriamine, alkyltetramine, pyrrolidine, piperazine, aminopiperazine, alkylpentamine, alkylhexamine and derivatives thereof is more preferable. As for carbon number of the said alkyl, 4-10 are mentioned, Preferably it is 6-8. Examples of typical alkyldiamines include 1,6-hexanediamine and 1,8-diaminooctane.

  The molar ratio ([Si] / [Al]) between silicon and aluminum constituting the organic template-containing zeolite having a 10-membered ring one-dimensional pore structure (hereinafter referred to as “Si / Al ratio”) is 10. It is preferable that it is -400, and it is more preferable that it is 20-350. When the Si / Al ratio is less than 10, the activity for the conversion of normal paraffin increases, but the isomerization selectivity to isoparaffin tends to decrease, and the increase in decomposition reaction accompanying the increase in reaction temperature tends to become rapid. Therefore, it is not preferable. On the other hand, when the Si / Al ratio exceeds 400, it is difficult to obtain the catalyst activity necessary for the conversion of normal paraffin, which is not preferable.

  The organic template-containing zeolite synthesized, preferably washed and dried usually has an alkali metal cation as a counter cation, and the organic template is included in the pore structure. The zeolite containing the organic template used in the production of the hydroisomerization dewaxing catalyst according to the present invention is used in order to remove the synthesized state, that is, the organic template included in the zeolite. It is preferable that the baking treatment is not performed.

  The organic template-containing zeolite is then ion exchanged in a solution containing ammonium ions and / or protons. By the ion exchange treatment, the counter cation contained in the organic template-containing zeolite is exchanged with ammonium ions and / or protons. At the same time, a part of the organic template included in the organic template-containing zeolite is removed.

  The solution used for the ion exchange treatment is preferably a solution using a solvent containing at least 50% by volume of water, and more preferably an aqueous solution. Examples of the compound that supplies ammonium ions into the solution include various inorganic and organic ammonium salts such as ammonium chloride, ammonium sulfate, ammonium nitrate, ammonium phosphate, and ammonium acetate. On the other hand, mineral acids such as hydrochloric acid, sulfuric acid and nitric acid are usually used as the compound for supplying protons into the solution. An ion-exchanged zeolite obtained by ion-exchange of an organic template-containing zeolite in the presence of ammonium ions (here, an ammonium-type zeolite) releases ammonia during subsequent calcination, and the counter cation serves as a proton as a brane. Stead acid point. As the cation species used for ion exchange, ammonium ions are preferred. The content of ammonium ions and / or protons contained in the solution is preferably set to be 10 to 1000 equivalents relative to the total amount of counter cation and organic template contained in the organic template-containing zeolite to be used. .

  The ion exchange treatment may be performed on the powdery organic template-containing zeolite alone, and prior to the ion exchange treatment, the organic template-containing zeolite is blended with an inorganic oxide as a binder, molded, and obtained. You may perform with respect to the molded object obtained. However, if the molded body is subjected to an ion exchange treatment without firing, the molded body is likely to collapse and pulverize, so the powdered organic template-containing zeolite can be subjected to an ion exchange treatment. preferable.

  The ion exchange treatment is preferably performed by an ordinary method, that is, a method in which a zeolite containing an organic template is immersed in a solution containing ammonium ions and / or protons, preferably an aqueous solution, and this is stirred or fluidized. Moreover, it is preferable to perform said stirring or a flow under a heating in order to improve the efficiency of ion exchange. In this embodiment, a method in which the aqueous solution is heated and ion exchange is performed under boiling and reflux is particularly preferable.

  Furthermore, from the viewpoint of increasing the efficiency of ion exchange, it is preferable to exchange the solution once or twice or more during the ion exchange of the zeolite with the solution, and exchange the solution once or twice. It is more preferable. In the case of changing the solution once, for example, the organic template-containing zeolite is immersed in a solution containing ammonium ions and / or protons, heated to reflux for 1 to 6 hours, and then replaced with a new one. By heating to reflux for ˜12 hours, the ion exchange efficiency can be increased.

  By the ion exchange treatment, almost all counter cations such as alkali metals in the zeolite can be exchanged for ammonium ions and / or protons. On the other hand, a part of the organic template included in the zeolite is removed by the above ion exchange treatment. However, it is generally difficult to remove all of the organic template even if the treatment is repeated. Part remains inside the zeolite.

  In this embodiment, a support precursor is obtained by heating a mixture containing ion-exchanged zeolite and a binder at a temperature of 250 to 350 ° C. in a nitrogen atmosphere.

  The mixture containing the ion exchange zeolite and the binder is preferably a mixture of the ion exchange zeolite obtained by the above method and an inorganic oxide as a binder and molding the resulting composition. The purpose of blending the inorganic oxide with the ion-exchanged zeolite is to improve the mechanical strength of the carrier (particularly, the particulate carrier) obtained by firing the molded body to such an extent that it can be practically used. The inventor has found that the choice of inorganic oxide species affects the isomerization selectivity of the hydroisomerization dewaxing catalyst. From such a viewpoint, the inorganic oxide is at least one selected from a composite oxide composed of alumina, silica, titania, boria, zirconia, magnesia, ceria, zinc oxide, phosphorus oxide, and combinations of two or more thereof. Inorganic oxides are used. Among these, silica and alumina are preferable and alumina is more preferable from the viewpoint of further improving the isomerization selectivity of the hydroisomerization dewaxing catalyst. The “composite oxide composed of a combination of two or more of these” is composed of at least two components of alumina, silica, titania, boria, zirconia, magnesia, ceria, zinc oxide, and phosphorus oxide. The composite oxide is preferably a composite oxide mainly composed of alumina containing 50% by mass or more of an alumina component based on the composite oxide, and more preferably alumina-silica.

  The mixing ratio of the ion exchange zeolite and the inorganic oxide in the composition is preferably 10:90 to 90:10, more preferably 30:70 to 85, as a ratio of the mass of the ion exchange zeolite to the mass of the inorganic oxide. : 15. When this ratio is smaller than 10:90, the activity of the hydroisomerization dewaxing catalyst tends to be insufficient. On the other hand, when the ratio exceeds 90:10, the mechanical strength of the carrier obtained by molding and baking the composition tends to be insufficient, which is not preferable.

  The method of blending the above-mentioned inorganic oxide with the ion-exchanged zeolite is not particularly limited. For example, it is usual to add a suitable amount of liquid such as water to both powders to form a viscous fluid and knead this with a kneader or the like. The method performed can be adopted.

  A composition containing the ion-exchanged zeolite and the inorganic oxide or a viscous fluid containing the composition is molded by a method such as extrusion molding, and preferably dried to form a particulate molded body. The shape of the molded body is not particularly limited, and examples thereof include a cylindrical shape, a pellet shape, a spherical shape, and a modified cylindrical shape having a trefoil / four-leaf cross section. The size of the molded body is not particularly limited, but from the viewpoint of ease of handling, packing density into the reactor, and the like, for example, the major axis is preferably about 1 to 30 mm and the minor axis is about 1 to 20 mm.

In this embodiment, the molded body obtained as described above is sufficiently dried at 100 ° C. or lower and subsequently heated in a N ₂ atmosphere at a temperature of 250 to 350 ° C. It is preferable to do. About heating time, 0.5 to 10 hours are preferable and 1 to 5 hours are more preferable.

  In this embodiment, when the heating temperature is lower than 250 ° C., a large amount of the organic template remains, and the pores of the zeolite are blocked by the remaining template. It is considered that the isomerization active site is present near the pore pore mouse. In the above case, the reaction substrate cannot diffuse into the pore due to the clogging of the pore, and the active site is covered and the isomerization reaction does not proceed easily. The conversion rate of normal paraffin tends to be insufficient. On the other hand, when the heating temperature exceeds 350 ° C., the isomerization selectivity of the resulting hydroisomerization dewaxing catalyst is not sufficiently improved.

  The lower limit temperature when the molded body is heated to form a carrier precursor is preferably 280 ° C. or higher. The upper limit temperature is preferably 330 ° C. or lower.

  In this aspect, it is preferable to heat the mixture so that a part of the organic template contained in the molded body remains. Specifically, the amount of carbon in the hydroisomerization dewaxing catalyst obtained through calcination after metal loading described later is 0.4 to 3.5% by mass (preferably 0.4 to 3.0% by mass, more Preferably 0.4 to 2.5% by mass, more preferably 0.4 to 1.5% by mass), or the micropore volume per unit mass of the catalyst is 0.02 to 0.3%. The heating conditions are preferably set so that the micropore volume per unit mass of the zeolite contained in the catalyst is 0.01 to 0.12 ml / g.

  Next, a catalyst precursor in which a platinum salt and / or a palladium salt is contained in the carrier precursor is 250 to 400 ° C., preferably 280 to 400 ° C., more preferably 300 to 400 in an atmosphere containing molecular oxygen. Calcination is carried out at a temperature of 0 ° C. to obtain a hydroisomerization dewaxing catalyst in which platinum and / or palladium is supported on a support containing zeolite. Note that “under an atmosphere containing molecular oxygen” means that the gas is in contact with a gas containing oxygen gas, preferably air. The firing time is preferably 0.5 to 10 hours, and more preferably 1 to 5 hours.

  Examples of the platinum salt include chloroplatinic acid, tetraamminedinitroplatinum, dinitroaminoplatinum, and tetraamminedichloroplatinum. Since the chloride salt generates hydrochloric acid during the reaction and may corrode the equipment, tetraamminedinitroplatinum, which is a platinum salt in which platinum is highly dispersed other than the chloride salt, is preferable.

  Examples of the palladium salt include palladium chloride, tetraamminepalladium nitrate, and diaminopalladium nitrate. Since the chloride salt generates hydrochloric acid during the reaction and may corrode the equipment, tetraamminepalladium nitrate, which is a palladium salt in which palladium is highly dispersed other than the chloride salt, is preferable.

  The supported amount of the active metal in the support including the zeolite according to this embodiment is preferably 0.001 to 20% by mass, and more preferably 0.01 to 5% by mass based on the mass of the support. When the supported amount is less than 0.001% by mass, it is difficult to provide a predetermined hydrogenation / dehydrogenation function. On the other hand, when the supported amount exceeds 20% by mass, lightening by decomposition of hydrocarbons on the active metal tends to proceed, and the yield of the target fraction tends to decrease, This is not preferable because the catalyst cost tends to increase.

  Further, when the hydroisomerization dewaxing catalyst according to this embodiment is used for hydroisomerization of a hydrocarbon oil containing a large amount of a sulfur-containing compound and / or a nitrogen-containing compound, an active metal is used from the viewpoint of sustainability of the catalyst activity. It is preferable to include a combination of nickel-cobalt, nickel-molybdenum, cobalt-molybdenum, nickel-molybdenum-cobalt, nickel-tungsten-cobalt, and the like. The supported amount of these metals is preferably 0.001 to 50% by mass, and more preferably 0.01 to 30% by mass based on the mass of the carrier.

  In this embodiment, the catalyst precursor is preferably calcined so that the organic template left on the carrier precursor remains. Specifically, the amount of carbon in the resulting hydroisomerization dewaxing catalyst is 0.4 to 3.5% by mass (preferably 0.4 to 3.0% by mass, more preferably 0.4 to 2.5%. %, More preferably 0.4 to 1.5% by mass), or the resulting hydroisomerization dewaxing catalyst has a micropore volume per unit mass of 0.02 to 0.12 ml / It is preferable to set the heating conditions so that the micropore volume per unit mass of the zeolite contained in the catalyst is 0.01 to 0.12 ml / g.

  In the present specification, the amount of carbon in the hydroisomerization dewaxing catalyst can be analyzed by combustion in an oxygen stream-infrared absorption method. Specifically, using a carbon / sulfur analyzer (for example, EMIA-920V manufactured by Horiba, Ltd.), the catalyst is burned in an oxygen stream, and the amount of carbon is determined by infrared absorption. be able to.

  The micropore volume per unit mass of the hydroisomerization dewaxing catalyst is calculated by a method called nitrogen adsorption measurement. That is, for the catalyst, the physical adsorption / desorption isotherm of nitrogen measured at the liquid nitrogen temperature (−196 ° C.) is analyzed. Specifically, the adsorption isotherm of nitrogen measured at the liquid nitrogen temperature (−196 ° C.) By analyzing by the -plot method, the micropore volume per unit mass of the catalyst is calculated. The micropore volume per unit mass of zeolite contained in the catalyst is also calculated by the above nitrogen adsorption measurement.

Micropore volume V _Z per unit mass of zeolite contained in the catalyst, for example, if the binder does not have a micropore volume, micropore volume per unit mass of the hydroisomerization dewaxing catalyst Can be calculated according to the following formula from the value V _{c of the above} and the content ratio M _z (mass%) of the zeolite in the catalyst.
V _Z = V _c / M _z × 100

  It is preferable that the hydroisomerization dewaxing catalyst of this embodiment is a catalyst that has been subjected to a reduction treatment after being charged into a reactor that performs a hydroisomerization reaction following the above-described calcination treatment. Specifically, hydrogen reduction treatment is performed for about 0.5 to 10 hours in an atmosphere containing molecular hydrogen, preferably in a hydrogen gas flow, preferably at 250 to 500 ° C., more preferably at 300 to 400 ° C. It is preferred that By such a process, the high activity with respect to dewaxing of hydrocarbon oil can be more reliably imparted to the catalyst.

  The hydroisomerization dewaxing catalyst of this embodiment contains a zeolite having a 10-membered ring one-dimensional pore structure, a support containing a binder, and platinum and / or palladium supported on the support. And the hydroisomerization dewaxing catalyst of this aspect is a catalyst whose carbon amount in a catalyst is 0.4-3.5 mass%. The hydroisomerization dewaxing catalyst of this embodiment is a hydroisomerization dewaxing catalyst having a micropore volume per unit mass of 0.02 to 0.12 ml / g, wherein the zeolite is an organic template. Is derived from ion-exchanged zeolite obtained by ion-exchange in a solution containing ammonium ions and / or protons, containing 10-membered ring one-dimensional pore structure and containing in the catalyst The zeolite may have a micropore volume per unit mass of 0.01 to 0.12 ml / g.

The hydroisomerization dewaxing catalyst of this embodiment can be produced by the method described above. The amount of carbon in the catalyst, the micropore volume per unit mass of the catalyst, and the micropore volume per unit mass of the zeolite contained in the catalyst are the blending amount of the ion exchange zeolite in the mixture containing the ion exchange zeolite and the binder. The heating conditions under the N ₂ atmosphere of the mixture and the heating conditions under the atmosphere containing molecular oxygen of the catalyst precursor can be adjusted within the above range by appropriately adjusting.

<Reaction conditions for the dewaxing process>
In the dewaxing step, the reaction temperature for isomerization dewaxing is preferably 200 to 450 ° C, more preferably 280 to 400 ° C. When the reaction temperature is lower than 200 ° C., the isomerization of normal paraffin contained in the base oil fraction is difficult to proceed, and the wax component tends to be insufficiently reduced and removed. On the other hand, when the reaction temperature exceeds 450 ° C., the decomposition of the base oil fraction becomes remarkable, and the yield of the lubricating base oil tends to decrease.

  The reaction pressure for isomerization dewaxing is preferably 0.1 to 20 MPa, and more preferably 0.5 to 15 MPa. When the reaction pressure is less than 0.1 MPa, the deterioration of the catalyst due to coke generation tends to be accelerated. On the other hand, when the reaction pressure exceeds 20 MPa, the cost for constructing the apparatus tends to be high, and it tends to be difficult to realize an economical process.

Liquid hourly space velocity for the base oil fraction of the catalyst in the isomerization dewaxing is preferably 0.01~100h ^-1, 0.1~50h ^-1 are more preferred. When the liquid space velocity is less than 0.01 h ⁻¹ , decomposition of the base oil fraction tends to proceed excessively and production efficiency tends to decrease. On the other hand, when the liquid space velocity exceeds 100 h ⁻¹ , isomerization of normal paraffin contained in the base oil fraction becomes difficult to proceed, and the reduction and removal of the wax component tend to be insufficient.

Supply ratio of hydrogen to base oil fraction in the isomerization dewaxing is preferably 100~1500Nm ³ / ^{m 3,} more preferably 200~800Nm ³ / ^{m 3.} When the supply ratio is less than 100 Nm ³ / m ³ , for example, when the base oil fraction contains a sulfur content or a nitrogen content, hydrogen sulfide and ammonia gas generated by desulfurization and denitrogenation combined with the isomerization reaction are on the catalyst. Since the active metal is adsorbed and poisoned, it tends to be difficult to obtain a predetermined catalyst performance. On the other hand, when the supply ratio exceeds 1000 Nm ³ / m ³ , a hydrogen supply facility with a large capacity is required, so that it is difficult to realize an economical process.

  The dewaxed oil obtained in the dewaxing step preferably has a normal paraffin concentration of 10% by volume or less, and more preferably 1% by volume or less.

  The dewaxed oil obtained in the dewaxing step in the present embodiment can be suitably used as a lubricant base oil raw material. In the present embodiment, for example, a hydrorefining step in which the dewaxed oil obtained in the dewaxing step is hydrorefined to obtain a hydrorefined oil, and the lubricating base oil is obtained by fractionating the hydrorefined oil. By obtaining the second separation step, a lubricating base oil can be obtained.

(Hydro-refining process)
In the hydrorefining step, the dewaxed oil obtained in the dewaxing step is hydrorefined to obtain a hydrorefined oil. Hydrorefining, for example, hydrogenates olefins and aromatics in the dewaxed oil, improving the oxidative stability and hue of the lubricating oil. Furthermore, a reduction in sulfur content is expected due to hydrogenation of sulfur compounds in the dewaxed oil.

  Hydrorefining can be performed by contacting the dewaxed oil with a hydrorefining catalyst in the presence of hydrogen. As the hydrorefining catalyst, for example, a support comprising one or more inorganic solid acidic substances selected from alumina, silica, zirconia, titania, boria, magnesia and phosphorus, and supported on the support, Examples thereof include a catalyst provided with one or more active metals selected from the group consisting of platinum, palladium, nickel-molybdenum, nickel-tungsten and nickel-cobalt-molybdenum.

  A suitable carrier is an inorganic solid acidic substance containing at least two kinds of alumina, silica, zirconia, or titania.

  As a method for supporting the active metal on the carrier, conventional methods such as impregnation and ion exchange can be employed.

  The supported amount of active metal in the hydrotreating catalyst is preferably such that the total amount of metal is 0.1 to 25% by mass with respect to the support.

  The average pore diameter of the hydrorefining catalyst is preferably 6 to 60 nm, and more preferably 7 to 30 nm. When the average pore diameter is smaller than 6 nm, sufficient catalytic activity tends to be not obtained, and when the average pore diameter exceeds 60 nm, the catalytic activity tends to decrease due to a decrease in the degree of dispersion of the active metal.

It is preferable that the pore volume of the hydrorefining catalyst is 0.2 mL / g or more. When the pore volume is less than 0.2 mL / g, the catalyst activity tends to be rapidly deteriorated. In addition, the pore volume of the hydrotreating catalyst may be 0.5 mL / g or less, for example. The specific surface area of the hydrotreating catalyst is preferably 200 m ² / g or more. When the specific surface area of the catalyst is less than 200 m ² / g, the dispersibility of the active metal is insufficient and the activity tends to decrease. The specific surface area of the hydrotreating catalyst may be 400 m ² / g or less, for example. The pore volume and specific surface area of these catalysts can be measured and calculated by a method called the BET method based on nitrogen adsorption.

The reaction conditions for the hydrorefining are preferably, for example, a reaction temperature of 200 to 300 ° C., a hydrogen partial pressure of 3 to 20 MPa, LHSV 0.5 to 5 h ⁻¹ , and a hydrogen / oil ratio of 170 to 850 Nm ³ / m ^3. ° C. to 300 ° C., a hydrogen partial pressure 4~18MPa, LHSV0.5~4h ^-1, more preferably a hydrogen / oil ratio 340~850Nm ³ / ^{m 3.}

  In the present embodiment, it is preferable to adjust the reaction conditions so that the sulfur content and the nitrogen content in the hydrorefined oil are 5 mass ppm or less and 1 mass ppm or less, respectively. The sulfur content is a value measured based on JIS K2541 “Crude oil and petroleum products—sulfur content test method”, and the nitrogen content is a value measured based on JIS K2609 “Crude oil and petroleum products—nitrogen content test method”.

(Second separation step)
In the second separation step, the hydrorefined oil is fractionally distilled to obtain a lubricating base oil.

  The distillation conditions in the second separation step are not particularly limited as long as the lubricating oil fraction can be fractionated from the hydrorefined oil. For example, in the second separation step, atmospheric distillation (or distillation under pressure) for distilling a light fraction from hydrorefined oil, and a lubricating oil fraction from the bottom oil of the atmospheric distillation are fractionated. It is preferable to be performed by vacuum distillation.

  In the second separation step, for example, by setting a plurality of cut points, the bottom oil obtained by atmospheric distillation (or distillation under pressure) of the hydrorefined oil is distilled under reduced pressure to obtain a plurality of lubrications. An oil fraction can be obtained. In the second separation step, for example, from the hydrorefined oil, a first lubricating oil fraction having a 10 vol% distillation temperature of 280 ° C or higher and a 90 vol% distillation temperature of 390 ° C or lower, and 10 vol% A second lubricating oil fraction having a distillation temperature of 390 ° C. or more and a 90% by volume distillation temperature of 490 ° C. or less; a 10% by volume distillation temperature of 490 ° C. or more and a 90% by volume distillation temperature of 530 ° C. or less; And the third lubricating oil fraction can be recovered by fractional distillation.

The first lubricating oil fraction can be obtained as a lubricating base oil suitable for ATF and shock absorbers. In this case, the kinematic viscosity at 100 ° C. is preferably 2.7 mm ² / s. The second lubricating oil fraction can be obtained as a lubricating base oil according to the present invention suitable for engine base oils that meet API Group III, III + standards, in this case kinematic viscosity at 100 ° C. It is preferable to use 0 mm ² / s as a target value, a fraction having a kinematic viscosity at 100 ° C. of 3.5 mm ² / s to 4.5 mm ² / s and a pour point of −20 ° C. or less. The third lubricating oil fraction is an engine oil base oil that satisfies API Group III, III + standards, and can be obtained as a lubricating base oil suitable for, for example, a diesel engine. It is preferable that the viscosity is a value higher than 32 mm ² / s, and the kinematic viscosity at 100 ° C. is higher than 6.0 mm ² / s. In the present specification, the kinematic viscosity and viscosity index at 40 ° C. or 100 ° C. are values determined based on JIS K2283 “Crude oil and petroleum products—Kinematic viscosity test method and viscosity index calculation method”.

  The first lubricating oil fraction is a lubricating base oil corresponding to 70 Pale, the second lubricating oil fraction is a lubricating base oil corresponding to SAE-10, and the third lubricating oil fraction is SAE- It can be obtained as a lubricating base oil corresponding to 20. SAE viscosity means a standard defined by Society of Automotive Engineers. The API standard is based on the classification of lubricating oil grades by the American Petroleum Institute (API), and is Group II (viscosity index of 80 to less than 120, saturation content of 90% by mass, and sulfur content. Content 0.03 mass% or less), group III (viscosity index 120 or more, saturation content 90 mass% or more, and sulfur content 0.03 mass% or less), group III + (viscosity index 140 or more, and , A saturation content of 90% by mass or more and a sulfur content of 0.03% by mass or less).

  The hydrorefined oil obtained in the hydrorefining step includes light fractions such as naphtha and kerosene produced as a by-product by hydroisomerization and hydrocracking. In the second separation step, these light fractions can be recovered, for example, as a fraction having a 90% by volume distillation temperature of 280 ° C. or less.

  In the present embodiment, a second separation step for fractionating the dewaxed oil obtained in the dewaxing step to obtain a lubricating oil fraction, and a hydrorefining step for hydrorefining the lubricating oil fraction, Thus, a lubricating base oil can be obtained. At this time, the second separation step and the hydrorefining step can be performed in the same manner as the above-described second separation step and hydrorefining step.

  Next, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a flowchart showing an example of a lubricating base oil production apparatus for carrying out the lubricating base oil production method of the present invention.

  The lubricating base oil production apparatus 100 shown in FIG. 1 includes a first reactor 10 for hydrocracking the feedstock introduced from the flow path L1, and hydrogen supplied from the first reactor through the flow path L2. A first separator 20 for high-pressure separation (fractionation under pressure) of the pyrolysis oil, a first vacuum distillation column 21 for vacuum distillation of bottom oil supplied from the first separator 20 through the flow path L3, A flow path L5 for supplying the base oil fraction fractionated in the first vacuum distillation tower 21 to the subsequent stage, and a flow path L6 for joining the heavy fraction fractionated in the first vacuum distillation tower 21 to the flow path L1. A second reactor 30 for isomerizing and dewaxing the base oil fraction supplied from the flow path L5, and a hydrotreating of the dewaxed oil supplied from the second reactor 30 through the flow path L7. 3 and the hydrorefined oil supplied from the third reactor 40 through the flow path L8. A second separator 50 to fractionation, and the bottom oil supplied through the passage L9 from the second separator 50 is configured to include a, a second vacuum distillation column 51 to vacuum distillation.

  Hydrogen gas is supplied to the first reactor 10, the second reactor 30, and the third reactor 40 through the flow path L40.

  The lubricating base oil manufacturing apparatus 100 is provided with a flow path L31 branched from the flow path L40 and connected to the flow path L1, and the hydrogen gas supplied from the flow path L31 is fed into the feed oil in the flow path L1. And introduced into the first reactor 10. A flow path L32 branched from the flow path L40 is connected to the first reactor 10, and the hydrogen pressure and the catalyst layer temperature in the first reactor 10 are increased by supplying hydrogen gas from the flow path L32. Adjusted.

  The lubricating base oil production apparatus 100 is also provided with a flow path L33 branched from the flow path L40 and connected to the flow path L5, and the hydrogen gas supplied from the flow path L33 is based on the flow path L5. It is mixed with the oil fraction and introduced into the second reactor 30. A flow path L34 branched from the flow path L40 is connected to the second reactor 30, and the hydrogen pressure and the catalyst layer temperature in the second reactor 30 are increased by supplying hydrogen gas from the flow path L34. Adjusted.

  The lubricating base oil production apparatus 100 further includes a flow path L35 branched from the flow path L40 and connected to the flow path L7. Hydrogen gas supplied from the flow path L35 is desorbed in the flow path L7. It is mixed with wax oil and introduced into the third reactor 40. Further, a flow path L36 branched from the flow path L40 is connected to the third reactor 40, and the hydrogen pressure and the catalyst layer temperature in the third reactor 40 are increased by the supply of hydrogen gas from the flow path L36. Adjusted.

  In addition, from the 2nd reactor 30, the hydrogen gas which passed the 2nd reactor 30 with the dewaxed oil is taken out by the flow path L7. Therefore, the amount of hydrogen gas supplied from the flow path L35 can be appropriately adjusted according to the amount of hydrogen gas taken out from the second reactor 30.

  The first separator 20 is connected to a flow path L4 for taking out a lighter fraction and hydrogen gas that are lighter than the base oil fraction. The mixed gas containing the light fraction and hydrogen gas taken out from the flow path L4 is supplied to the first gas-liquid separator 60 and separated into the light fraction and hydrogen gas. The first gas-liquid separator 60 is connected to a flow path L21 for taking out a light fraction and a flow path L22 for taking out hydrogen gas.

  The second separator 50 is connected to a flow path L10 for taking out a lighter fraction and hydrogen gas that are lighter than the lubricating base oil. The mixed gas containing the light fraction and hydrogen gas taken out from the flow path L10 is supplied to the second gas-liquid separator 70 and separated into the light fraction and hydrogen gas. The second gas-liquid separator 70 is connected to a flow path L23 for taking out a light fraction and a flow path L24 for taking out hydrogen gas.

  The hydrogen gas taken out from the first gas-liquid separator 60 and the second gas-liquid separator 70 is supplied to the acid gas absorption tower 80 through the flow path L22 and the flow path L24. The hydrogen gas taken out from the first gas-liquid separator 60 and the second gas-liquid separator 70 contains hydrogen sulfide, which is a hydride of sulfur, and the acidic gas absorption tower 80 Remove hydrogen sulfide and the like. The hydrogen gas from which hydrogen sulfide or the like has been removed by the acid gas absorption tower 80 is supplied to the flow path L40 and is reintroduced into each reactor.

  The second vacuum distillation column 51 is provided with flow paths L11, L12, and L13 for taking out the lubricating oil fraction fractionated according to the desired lubricating base oil out of the system.

  In the lubricant base oil production apparatus 100, the hydrocracking step can be performed by hydrocracking the raw material oil supplied from the flow path L <b> 1 in the first reactor 10. In the first reactor 10, hydrocracking can be performed by bringing the raw material oil into contact with the hydrocracking catalyst in the presence of hydrogen (molecular hydrogen) supplied from the flow path L 31 and the flow path L 32.

  The form of the 1st reactor 10 is not specifically limited, For example, the fixed bed flow-type reactor filled with the hydrocracking catalyst is used suitably. In the lubricating base oil production apparatus 100, the only reactor for hydrocracking is the first reactor 10, but in this embodiment, the lubricating base oil production apparatus is used for hydrocracking. A plurality of reactors may be arranged in series or in parallel. Further, the catalyst bed in the reactor may be single or plural.

  In the lubricating base oil production apparatus 100, the first separation step can be performed by the first separator 20 and the first vacuum distillation tower 21.

  In the first separator 20, the hydrocracked oil supplied from the flow path L2 is subjected to high-pressure separation (distillation under pressure), whereby a light fraction is taken out from the flow path L4 and a bottom oil (base oil fraction and Heavy fraction) can be taken out from the flow path L3. In addition, hydrogen gas that has passed through the first reactor 10 together with the hydrocracked oil flows from the flow path L2 to the first separator 20. In the 1st separator 20, the said hydrogen gas can be taken out from the flow path L4 with a light fraction.

  In the first vacuum distillation tower 21, the bottom oil supplied from the flow path L3 is distilled under reduced pressure, whereby the base oil fraction can be taken out from the flow path L5 and the heavy fraction can be taken out from the flow path L6. The flow path L6 is connected to the flow path L1, and the extracted heavy fraction is joined to the flow path L1 and recycled as raw material oil. In the first vacuum distillation column 21, a fraction lighter than the base oil fraction may be extracted from the flow path L4 'and merged with the flow path L4.

  In the lubricating base oil production apparatus 100, the first separation step is performed by the first separator 20 and the first vacuum distillation column 21, but the first separation step is performed by, for example, three or more distillation columns. It can also be implemented. Further, the base oil fraction is taken out as a single fraction in the first vacuum distillation column 21, but in the manufacturing method according to the present embodiment, the base oil fraction is fractionated into two or more and taken out respectively. You can also.

  In the lubricant base oil production apparatus 100, the dewaxing process is performed in the second reactor 30. In the second reactor 30, the base oil fraction supplied from the channel L5 is brought into contact with the hydroisomerization dewaxing catalyst in the presence of hydrogen (molecular hydrogen) supplied from the channel L33 and the channel L34. Let Thereby, the base oil fraction is dewaxed by hydroisomerization.

  The type of the second reactor 30 is not particularly limited. For example, a fixed bed flow reactor filled with a hydroisomerization dewaxing catalyst is preferably used. In the lubricant base oil production apparatus 100, the only reactor for isomerization dewaxing is the second reactor 30, but in this embodiment, the lubricant base oil production apparatus is an isomerization dewaxing reactor. A plurality of reactors may be arranged in series or in parallel. Further, the catalyst bed in the reactor may be single or plural.

  The dewaxed oil obtained through the second reactor 30 is supplied to the third reactor 40 through the flow path L7 together with the hydrogen gas that has passed through the second reactor 30.

  In the lubricating base oil production apparatus 100, the hydrorefining step is performed in the third reactor 40. In the third reactor 40, the dewaxed oil supplied from the flow path L7 is brought into contact with the hydrotreating catalyst in the presence of hydrogen (molecular hydrogen) supplied from the flow path L7, the flow path L35, and the flow path L36. By doing so, the dewaxed oil is hydrorefined.

  The form of the 3rd reactor 40 is not specifically limited, For example, the fixed bed flow-type reactor filled with the hydrorefining catalyst is used suitably. In the lubricant base oil production apparatus 100, the only reactor for hydrorefining is the third reactor 40. However, in this embodiment, the lubricant base oil production apparatus is used for hydrorefining. A plurality of reactors may be arranged in series or in parallel. Further, the catalyst bed in the reactor may be single or plural.

  The hydrorefined oil obtained through the third reactor 40 is supplied to the second separator 50 through the flow path L8 together with the hydrogen gas that has passed through the third reactor 40.

  In the lubricant base oil manufacturing apparatus 100, the second separation step can be performed by the second separator 50 and the second vacuum distillation column 51.

  In the second separator 50, the hydrorefined oil supplied through the flow path L8 is subjected to high-pressure separation (fractionation under pressure), so that a fraction that is lighter than a fraction useful as a lubricant base oil (for example, naphtha). And the fuel oil fraction) can be taken out from the flow path L10, and the bottom oil can be taken out from the flow path L9. In addition, hydrogen gas that has passed through the third reactor 40 is circulated from the flow path L8 together with the hydrorefined oil. In the second separator 50, the hydrogen gas is extracted from the flow path L10 together with the light fraction. be able to.

  In the second vacuum distillation column 51, the bottom oil supplied from the flow path L9 is distilled under reduced pressure, whereby the lubricating oil fraction can be taken out from the flow paths L11, L12, and L13. Each of the lubricating oil fractions taken out from can be suitably used as a lubricating oil base oil. In the second vacuum distillation column 51, a fraction lighter than the lubricating oil fraction may be extracted from the flow path L10 'and merged with the flow path L10.

  In the lubricating base oil production apparatus 100, the second separation step is performed by the second separator 50 and the second vacuum distillation column 51. The second separation step is performed by, for example, three or more distillation columns. It can also be implemented. In the second vacuum distillation column 51, three fractions are fractionated and taken out as the lubricating oil fraction, but in the manufacturing method according to the present embodiment, a single fraction is taken out as the lubricating oil fraction. Alternatively, two fractions or four or more fractions may be fractionated as the lubricating oil fraction.

  In the lubricating base oil production apparatus 100, hydrocracking is performed in the first reactor 10 such that the cracking rate of heavy components is 20 to 85 mass%. At this time, the sulfur content contained in the raw material oil may be hydrogenated to generate hydrogen sulfide. That is, the hydrogen gas that has passed through the first reactor 10 may contain hydrogen sulfide.

  When the hydrogen gas containing hydrogen sulfide passes through the first reactor 10 and is returned to the flow path L40 as it is for recycling, the hydrogen gas containing hydrogen sulfide is supplied to the second reactor 30 and the second reactor is supplied. The catalytic activity of 30 is reduced. Therefore, in the lubricating base oil production apparatus 100, the hydrogen gas that has passed through the first reactor 10 flows into the flow path L2, the first separator 20, the flow path L4, the first gas-liquid separator 60, and the flow path L22. After being supplied to the acidic gas absorption tower 80, hydrogen sulfide is removed by the acidic gas absorption tower 80, and then returned to the flow path L40.

  Further, in the lubricating base oil production apparatus 100, the hydrogen gas that has passed through the second reactor 30 and the third reactor 40 may also contain hydrogen sulfide generated from the sulfur content slightly contained in the base oil fraction. Therefore, after being supplied to the acid gas absorption tower 80 through the flow path L24, it is returned to the flow path L40.

  In the lubricating base oil production apparatus 100, hydrogen gas is circulated through the acidic gas absorption tower 80 as described above. However, in the present embodiment, it is not always necessary to circulate hydrogen gas, and each reactor is respectively circulated. Hydrogen gas may be supplied independently.

  Further, the lubricating base oil production apparatus 100 may be provided with a wastewater treatment facility for removing ammonia or the like generated by hydrogenation of nitrogen contained in the raw material oil at the front stage or the rear stage of the acid gas absorption tower 80. Good. Ammonia is mixed with stripping steam or the like and processed in a wastewater treatment facility, converted into NOx together with sulfur by sulfur recovery, and then returned to nitrogen by denitration reaction.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, one aspect of the present invention is a manufacturing apparatus for performing the manufacturing method according to the present embodiment, and another aspect of the present invention relates to a lubricating base oil obtained by the manufacturing method according to the present embodiment. .

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to an Example.

(Production Example 1: Preparation of hydrocracking catalyst a)
Water was added to a mixture of 50% by mass of silica zirconia and 50% by mass of an alumina binder, and kneaded into a clay to prepare a kneaded product. This kneaded product was extruded, dried and fired to prepare a carrier. This support was loaded with 5% by weight of nickel oxide, 20% by weight of molybdenum oxide, and 3% by weight of phosphorus oxide by impregnation to obtain a hydrocracking catalyst a.

(Production Example 2: Preparation of hydroisomerization dewaxing catalyst b)
<Production of ZSM-22 zeolite>
ZSM-22 zeolite composed of crystalline aluminosilicate having a Si / Al ratio of 45 (hereinafter sometimes referred to as “ZSM-22”) was produced by hydrothermal synthesis according to the following procedure. First, the following four types of aqueous solutions were prepared.
Solution A: 1.94 g of potassium hydroxide dissolved in 6.75 mL of ion exchange water.
Solution B: A solution obtained by dissolving 1.33 g of aluminum sulfate 18-hydrate in 5 mL of ion-exchanged water.
Solution C: A solution obtained by diluting 4.18 g of 1,6-hexanediamine (organic template) with 32.5 mL of ion-exchanged water.
Solution D: 18 g of colloidal silica (Ludox AS-40 manufactured by Grace Davison) diluted with 31 mL of ion-exchanged water.

  Next, solution A was added to solution B and stirred until the aluminum component was completely dissolved. After adding the solution C to this mixed solution, the mixture of the solutions A, B and C was poured into the solution D with vigorous stirring at room temperature. Further, 0.25 g of ZSM-22 powder synthesized separately and not subjected to any special treatment after synthesis was added as a “seed crystal” for promoting crystallization, thereby obtaining a gel-like product.

  The gel obtained by the above operation is transferred to a stainless steel autoclave reactor having an internal volume of 120 mL, and the autoclave reactor is rotated on a tumbling apparatus at a rotation speed of about 60 rpm in an oven at 150 ° C. for 60 hours. The hydrothermal synthesis reaction was performed. After completion of the reaction, the reactor was cooled and opened, and dried overnight in a dryer at 60 ° C. to obtain ZSM-22 having a Si / Al ratio of 45.

<Ion exchange of ZSM-22 containing organic template>
The ZSM-22 obtained above was subjected to ion exchange treatment with an aqueous solution containing ammonium ions by the following operation.

  ZSM-22 obtained above was placed in a flask, 100 mL of 0.5N ammonium chloride aqueous solution was added to 1 g of ZSM-22 zeolite, and heated to reflux for 6 hours. After cooling this to room temperature, the supernatant was removed and the crystalline aluminosilicate was washed with ion-exchanged water. To this, the same amount of 0.5N-ammonium chloride aqueous solution as above was added again, and the mixture was refluxed with heating for 12 hours.

Thereafter, the solid content was collected by filtration, washed with ion-exchanged water, and dried overnight in a dryer at 60 ° C. to obtain ion-exchanged NH ₄ type ZSM-22. This ZSM-22 is ion-exchanged in a state containing an organic template.

<Binder formulation, molding, firing>
NH ₄ type ZSM-22 obtained above and alumina as a binder were mixed at a mass ratio of 7: 3, and a small amount of ion-exchanged water was added thereto and kneaded. The obtained viscous fluid was filled into an extrusion molding machine and molded to obtain a cylindrical molded body having a diameter of about 1.6 mm and a length of about 10 mm. This molded body was heated at 300 ° C. for 3 hours under a nitrogen atmosphere to obtain a carrier precursor.

<Platinum support, firing>
Tetraamminedinitroplatinum [Pt (NH ₃ ) ₄ ] (NO ₃ ) ₂ was dissolved in ion-exchanged water corresponding to the previously measured water absorption of the carrier precursor to obtain an impregnation solution. This solution was impregnated with the above carrier precursor by an initial wetting method, and supported so that the amount of platinum was 0.3 mass% with respect to the mass of ZSM-22 zeolite. Next, the impregnated material (catalyst precursor) obtained was dried overnight at 60 ° C. and then calcined at 400 ° C. for 3 hours under air flow to obtain a hydroisomer having a carbon content of 0.56% by mass. The dewaxing catalyst b was obtained. The amount of carbon in the hydroisomerization catalyst was analyzed by combustion in an oxygen stream-infrared absorption method (measuring device: EMIA-920V, Horiba, Ltd.). Specifically, the catalyst b was burned in an oxygen stream, and the amount of carbon was determined by an infrared absorption method.

Furthermore, the micropore volume per unit mass of the obtained hydroisomerization dewaxing catalyst was calculated by the following method. First, in order to remove water adsorbed on the hydroisomerization dewaxing catalyst, pretreatment was performed by evacuating at 150 ° C. for 5 hours. About the hydroisomerization dewaxing catalyst after this pre-treatment, adsorption and desorption is performed by a constant volume gas adsorption method using nitrogen at a liquid nitrogen temperature (-196 ° C.) using BELSORP-max manufactured by Nippon Bell Co., Ltd. The isotherm was automatically measured. For analysis of the data, using the analysis software (BEL Master ^™ ) attached to the apparatus, the measured nitrogen adsorption / desorption isotherm was automatically analyzed by the t-plot method, and the unit mass of the hydroisomerization dewaxing catalyst The per micropore volume (ml / g) was calculated.

Moreover, to calculate the micropore volume V _Z per unit mass of zeolite contained in the catalyst according to the following formula. In addition, when nitrogen adsorption measurement was performed similarly to the above about the alumina used as a binder, it was confirmed that an alumina does not have a micropore.
V _Z = Vc / Mz × 100
In the formula, Vc represents the micropore volume per unit mass of the hydroisomerization dewaxing catalyst, and Mz represents the content (mass%) of the zeolite contained in the catalyst.

  The micropore volume per unit mass of the hydroisomerization dewaxing catalyst b is 0.055 ml / g, and the micropore volume per unit mass of the zeolite contained in the catalyst is 0.079 ml / g. there were.

(Production Example 3: Hydrorefining catalyst c)
Water was added to a mixture of 50% by mass of silica zirconia and 50% by mass of an alumina binder, and kneaded into a clay to prepare a kneaded product. This kneaded product was extruded, dried and fired to prepare a carrier. This support was loaded with 0.3% by weight of platinum and 0.3% by weight of palladium by an impregnation method to obtain a hydrotreating catalyst c.

(Example A1)
Hereinafter, an embodiment will be described with reference to the lubricating base oil production apparatus 100 shown in FIG.
In Example 1, slack wax 1 shown in Table 1 was used as a new raw material (fresh feed, hereinafter referred to as “FF” in some cases). The slack wax was reacted at a temperature of 382 ° C., a hydrogen partial pressure of 11 MPa, and a liquid space velocity. Hydrocracked at (LHSV) 0.5 h ⁻¹ , hydrogen / oil ratio 844 Nm ³ / m ³ . Hydrocracking catalyst a was used as the hydrocracking catalyst, and the cracking rate was 67% under the hydrocracking conditions.

  The obtained hydrocracked oil was fractionated into a fraction with a boiling point of 290 ° C. or less (light fraction) and a fraction with a higher fraction (bottom oil) in a high-temperature and high-pressure separator (first separator 20). The light fraction is separated into a gas component mainly containing hydrogen gas and a liquid fraction (cracked oil) by a gas-liquid separator (first gas-liquid separator 60), and the gas component is an acid gas absorption tower (acid gas). It is guided to an absorption tower 80) to absorb and remove impurities such as hydrogen sulfide and ammonia to form hydrogen gas, and then mixed with fresh hydrogen gas as appropriate to hydrocracking reaction tower (first reactor 10), isomerization It introduced into the reaction tower (2nd reactor 30) and the hydrofinishing reaction tower (3rd reactor 40).

  On the other hand, the bottom oil was fractionated into a fraction having a boiling point of 530 ° C. or lower (base oil fraction) and a boiling point fraction having a higher boiling point (heavy fraction) by distillation under reduced pressure. A heavy fraction (hereinafter referred to as “RF” in some cases) is recycled and mixed with slack wax 1 (slack wax 1: heavy fraction = 33: 67 (mass ratio)), and a hydrocracking reaction tower. Supplied to. That is, in Example 1, a mixture of slack wax 1 and a heavy fraction (hereinafter sometimes referred to as “CF”) was used as a raw material oil except at the start.

Next, the base oil fraction (hereinafter, referred to as “LF” in some cases) is subjected to a reaction temperature of 300 ° C., a hydrogen partial pressure of 5.5 MPa, a liquid space velocity of 1 h ⁻¹ , and a hydrogen / oil ratio of 505 Nm ³ / m ³ . Isomerization dewaxing gave a dewaxed oil. The hydroisomerization dewaxing catalyst b was used as the hydroisomerization dewaxing catalyst. Next, the dewaxed oil is hydrorefined under the conditions of a reaction temperature of 223 ° C., a hydrogen partial pressure of 5 MPa, a liquid space velocity of 1.5 h ⁻¹ , and a hydrogen / oil ratio of 505 Nm ³ / m ^3. Obtained. The hydrotreating catalyst c was used as the hydrotreating catalyst. The hydrorefined oil has a 10 vol% distillation temperature of 280 ° C or higher and a 90 vol% distillation temperature of 390 in a distillation column (high-temperature high-pressure separator (second separator 50) and second vacuum distillation column 51). Lubricating base oil 1, 10 vol% distillation temperature is 390 ° C or higher, and 90 vol% distillation temperature is 490 ° C or lower, and 10 vol% distillation temperature is 490 ° C or higher. In addition, the base oil 3 was subjected to fractional distillation at the 90% by volume distillation temperature of 530 ° C. or lower to obtain lubricating base oils 1 to 3. The operation was continued for 200 hours under these process conditions, and the properties and yield of each lubricating base oil were determined.

  Table 1 shows the properties of the slack wax 1 (FF properties), and Table 2 shows the properties of the feed oil (CF) that is a mixture of the slack wax 1 (FF) and the heavy fraction (RF). Table 4 shows hydrocracking conditions and properties of the obtained base oil fraction (LF). Table 6 shows hydroisomerization conditions and hydrorefining conditions. Table 8 shows the properties of the lubricating base oils 1 to 3 and the yield of each lubricating base oil.

  In the table, “LF / FF selectivity” is the ratio of the total amount of the obtained base oil fraction (LF) to the total amount of the new raw material (FF) supplied to the hydrogenation reaction tower per unit time ( Mass%). The “yield to LF” in each lubricating base oil is the ratio of the total amount of lubricating base oil to the total amount of base oil fraction (LF) subjected to hydroisomerization dewaxing per unit time ( "Total yield 1" is a ratio of the total amount of the obtained lubricant base oils 1 to 3 to the total amount of the feedstock (CF) supplied to the hydrocracking reaction tower per unit time ( "Total yield 2" is the ratio (mass%) of the total amount of the obtained lubricant base oils 1 to 3 to the total amount of the new raw material (FF) subjected to the process per unit time. Indicates.

(Examples A2 to A5, Comparative Examples a1 to a2)
Continuous 200 as in Example A1, except that the FF / RF ratio, hydrocracking conditions, hydroisomerization conditions and hydrorefining conditions in the feedstock (CF) were changed as shown in Tables 2-7. A time process was implemented. The properties of the obtained lubricating base oils 1 to 3 and the yield of each lubricating base oil were as shown in Tables 8 and 9.

In the table, “T10 (° C.)” and “T90 (° C.)” are 10% by volume distillation temperature and 90% by volume distillation measured according to JIS K2254 “Petroleum products—Distillation test method—Gas chromatographic method”. Indicates the temperature of the temperature. “Density @ 15 ° C. (g / cm ³ )” indicates a value of density at 15 ° C. measured based on JIS K2254 “Crude oil and petroleum products—density test method and density / mass / capacity conversion table”. Further, “100 ° C. kinematic viscosity (mm ² / s)” indicates a value of kinematic viscosity at 100 ° C. measured based on JIS K2283 “Crude oil and petroleum products—Kinematic viscosity test method and viscosity index calculation method”. “Sulfur content (mass%)” indicates the sulfur content measured based on JIS K2541 “Crude oil and petroleum products—Sulfur content test method”. Further, “nitrogen content (mass ppm)” indicates the nitrogen content measured based on JIS K2609 “Crude oil and petroleum products—nitrogen content test method”. In addition, “C30 or more (mass%)” and “C30-60 (mass%)” were equipped with a nonpolar column (Ultra Alloy-1HT (30 m × 0.25 mmφ), FID (hydrogen flame ionization detector). The content ratio of hydrocarbons having 30 or more carbon atoms and the content ratio of hydrocarbons having 30 to 60 carbon atoms, which are obtained based on the component analysis results separated and quantified by Gas Chromatograph GC-2010 manufactured by Shimadzu Corporation, are shown.

In the table, “100 ° C. kinematic viscosity (mm ² / s)” and “viscosity index” are measured based on JIS K2283 “crude oil and petroleum products—kinematic viscosity test method and viscosity index calculation method”, 100 ° C. The kinematic viscosity value and the viscosity index value are shown. The “pour point (° C.)” indicates a pour point value measured based on JIS K2269 “Crude point of crude oil and petroleum products and cloud point test method of petroleum products”.

(Examples B1 to B4 and Comparative Examples b1 to b2)
The slack wax 1 is changed to the slack wax 2 shown in Table 10, and the FF / RF ratio, hydrocracking conditions, hydroisomerization conditions and hydrorefining conditions in the feedstock oil (CF) are shown in Tables 11-16. A continuous 200-hour process was carried out in the same manner as in Example A1 except that it was as described above. The properties of the obtained lubricating base oils 1 to 3 and the yield of each lubricating base oil were as shown in Table 17 and Table 18.

DESCRIPTION OF SYMBOLS 10 ... 1st reactor, 20 ... 1st separator, 21 ... 1st vacuum distillation tower, 30 ... 2nd reactor, 40 ... 3rd reactor, 50 ... 2nd separator, 51 ... 1st 2 vacuum distillation towers, 60 ... first gas-liquid separator, 70 ... second gas-liquid separator, 80 ... acid gas absorption tower, L1, L2, L3, L4, L4 ', L5, L6, L7, L8, L9, L10, L10 ′, L11, L12, L13, L21, L22, L23, L24, L31, L32, L33, L34, L35, L36, L40...

Claims (8)

Hydrogenation of a heavy oil having a carbon content of 30 or more with a hydrogen partial pressure of 5 to 20 MPa under a hydrogen partial pressure of 5 to 20 MPa so that the decomposition ratio of the heavy component is 20 to 85 mass%. A first step of performing cracking to obtain a hydrocracked oil containing the heavy component and a hydrocracked product thereof;
Second step of fractionating a base oil fraction containing the hydrocracked product and a heavy fraction containing the heavy fraction and heavier than the base oil fraction from the hydrocracked oil, respectively. When,
A third step of obtaining a dewaxed oil by bringing the base oil fraction fractionated in the second step into contact with a hydroisomerization dewaxing catalyst to isomerize and dewax;
With
The hydroisomerization dewaxing catalyst contains a zeolite having a 10-membered ring one-dimensional pore structure, a support containing a binder, platinum and / or palladium supported on the support, and the amount of carbon is A hydroisomerization dewaxing catalyst of 0.4 to 3.5% by mass,
The zeolite is derived from an ion exchange zeolite obtained by ion exchange of an organic template-containing zeolite containing an organic template and having a 10-membered ring one-dimensional pore structure in a solution containing ammonium ions and / or protons. And
A method for producing a lubricating base oil, wherein the heavy fraction fractionated in the second step is returned to the first step as part of the feedstock.   The manufacturing method of Claim 1 whose content rate of the sulfur content in the said raw material oil is 0.0001-3.0 mass%. A fourth step of hydrorefining the dewaxed oil obtained in the third step to obtain a hydrorefined oil;
The manufacturing method according to claim 1, further comprising: a fifth step of fractionating the hydrorefined oil obtained in the fourth step to obtain a lubricating base oil. The manufacturing method according to claim 3, wherein in the fifth step, a lubricating base oil having a kinematic viscosity at 100 ° C of 3.5 mm ² / s to 4.5 mm ² / s and a viscosity index of 120 or more is obtained. The raw material oil includes slack wax having a 10% by volume distillation temperature of 500 to 600 ° C and a 90% by volume distillation temperature of 600 to 700 ° C,
The manufacturing method according to any one of claims 1 to 4, wherein, in the first step, the hydrocracking is performed such that a decomposition rate of the heavy component is 25 to 85% by mass. The raw material oil contains slack wax having a 10 vol% distillation temperature of 400 to 500 ° C and a 90 vol% distillation temperature of 500 to 600 ° C,
The manufacturing method according to any one of claims 1 to 4, wherein in the first step, the hydrocracking is performed so that a decomposition rate of the heavy component is 20 to 80% by mass.   In the presence of hydrogen, the hydrocracking is carried on a porous inorganic oxide comprising two or more elements selected from aluminum, silicon, zirconium, boron, titanium and magnesium, and the porous inorganic oxide. Any one of Claims 1-6 performed by making the said raw material oil contact with the hydrocracking catalyst containing 1 or more types of metals chosen from the periodic table group 6 and 8-10 group element which were made The manufacturing method according to one item. Micropore volume is 0.02~0.12ml / g der before Symbol hydroisomerization dewaxing catalyst is,
Wherein a micro pore volume 0.01~0.12ml / g per unit mass of zeolite, method for producing a lubricant base oil according to any one of claims 1 to 7.

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